Hitherto, bearing walls including joined wall surface members, such as steel sheets on frame members, have been employed in buildings such as steel houses or pre-fabricated homes (see, for example, Japanese Patent No. 3737368). Such bearing walls are designed so that, when applied with an earthquake load, sheer stress occurs in a wall surface member, and an axial force occurs in a frame member.
The bearing wall described in Japanese Patent No. 3737368 is configured by a frame assembled into a rectangular shaped frame of frame members around the periphery of a steel sheet (wall surface member), and by cross-members provided inside the frame. Plural holes are formed in regions of the steel sheet (the wall surface member) other than portions where the frame members are joined, distributed in the height direction and the horizontal direction (width direction). Ribs integrated to the steel sheet are formed with circular tube shapes or truncated circular cone shapes at the edge portions of these holes. The ribs are formed to reinforce the external face of the steel sheet.